The Molecule of More: How a Single Chemical in Your Brain Drives Love, Sex, and Creativity―and Will Determine the Fate of the Human Race

by Daniel Z. Lieberman

They’re ambivalent: part of them wants nothing more than to use drugs, but there are other, weaker desires as well. Those desires can be strengthened. There may be a desire to be a better spouse, a better parent, or to do better at work.